Those fires in California are more because of climate, not land use practices

Forest fires are scary things. We humans want to put them out. Perhaps some of us were influenced by the terrifying fire in Bambi, and certainly Smoky the Bear's stern warning, "Only YOU can prevent forest fires" had an impact on my generation. But even without the propaganda, a fire is so powerful, unpredictable and destructive that we're right to be afraid.

It's common to hear that our land use practices, particularly the way we suppress natural fires, are the reason for so many fires in the USA and Canada. In the days before the European colonization here, lightning and other natural causes started fires, which burned and regenerated both forests and grasslands. With fire suppression comes a build-up of fuel and ultimately, more intense fires.

A paper published in August 2006 in the journal Science, "Warming and Earlier Spring Increase Western U.S. Forest Wildfire Activity" by A. L. Westerling, H. G. Hidalgo, D. R. Cayan and T. W. Swetnam studied the relationship between fires and climate.

The overall conclusion is that climate - less water, warmer temperatures - causes fires even where land management hasn't changed over the centuries. The recent (since the mid-1980s) warm climate and the increase in forest fires in the study area are related.

Here are the details from Science to help you locate the original paper.

http://www.sciencemag.org/cgi/rapidpdf/1128834.pdf
full/1128834/DC1
Materials and Methods
Figs. S1 to S3
References
17 April 2006; accepted 28 June 2006
Published online 6 July 2006;
10.1126/science.1128834
Include this information when citing this paper.
RESEARCH ARTICLES
www.sciencemag.org SCIENCE VOL 313 18 AUGUST 2006 943